Switchboard structure



June 2. 1925 7 1,539,847

w. H. KEMPTON SWITCHBOARD STRUCTURE Filed July 1. 922

WITNESSES: Q W1 d MENTOR +0" l a! 8m 5 BY p i r; ATTORNEY Patented June 2, 19 25.

1 UNITED STAT'ESPATENT OFFICE.

WILLAR n. KEMPTON, or WILKINSBURG, PENNSYLVANIA, ASSIGNOR T0, wns'r- INGHOUSE ELECTRIC & MANUFACTURING COMPANY, a oonronarron or PENN- SYLVANIA.

SWITCHBOARD STRUCTURE.

Application filed July 13, 1322. Serial No. 574,761.

To all whom it may concern.-

Be it known that I, VILLARD H. KEMP- roN, a citizen of the United States, and a resident of VVilkinsburg, in the countyof Allegheny and State of Pennsylvania, have invented a new anduseful Improvement in Switchboard Structures, of which the following is a specification." j

My invention relates to switchboard structurns and particularly to structures for securing an [insulating instrument base to :1 switchboard or insulating panel.

One object of'my invention'is to provide a fastening means for attaching an insulat- .ing instrument base to an insulating switchboard or panel in such man'ner'that the strain imposed by the fastening members is uniformly distributed,,thus eliminating the danger of fracture of the insulating base.

Another object of my invention is to provide a structure, "having the above characteristics, that is inexpensive to manufacture and which maybe readily applied to stand ard switchboards and base structures.

In certain installations, it has been customaryto secure the instrument base'to a switchboard by means of threaded bolts, the

base being drawn securelyagainstthe outer face of the switchboard or panel. In commercial structures'of this character, surfaces of the rear face of the insulating base are usually uneven and the surfaces of the switchboard may be warped out of a true plane. In such cases the insulating base, when drawn into engagement with the switchboard or panel, is subjected to uneven strains and frequently is fractured during the assembly operation. Fractures may also occur after the base has been assembled and after the switchboard has been shipped in consequence of such uneven stresses.

These and other objects, that will be made apparent throughout the further description of my invention, are attained by means of the switchboard structures hereinafter described, and illustrated in the accompanying d awings, wherein Figure 1 is a plan view of a base, member assembled upon a switchboard or panel;

Fig. 2 is a view, partially in elevation and partially in vertical section, of the fastening mechanism and the base and panel structures;

Fig. 3 is a vertical section through a panel and base, showing a modified form of fas mounted upon the insulating base. The

support 5 and the base 6 are provided with perforations 7 and 8, respectively, into which four fastening members 9 are inserted. The heads 11 of the bolts are maintained in a fixed predetermined spaced relation to the support 5 by means of metal sleeveslQ that are slidably mounted upon the bolts 9 and are clamped between the heads 11 and the support '5 when the nuts 13 are tightened; o

It will be seen that the base 6 is, there fore, slidably mounted for movement l0ngitudinally of the bolts between the'heads 11 andthe support 5. Spring washers 14: are mounted on the bolts between the base and the support to yieldingly press the base'b into engagement with the heads ll of the bolts.

The base is, therefore, yieldingly supported in spaced relation to the switchboard'or support 15. The resilient pressure exerted by the spring washers is sufiicient to firmly retain the base -6 in a fixed position against the heads of the bolts but, at no time, is it sutlicient to cause fracture of the base, regardless of the irregularities of the surfaces of the base. The sleeves 12 preventcompression of the spring washers beyond a predetermined limit and, therefore, the danger of fracture of the base is eliminated.

Fig. 8 shows a modified form of fastening member wherein the shank 15 of the bolt is of greater diameter than the threaded portion 16 thereof. A shoulder 17 is provided by this construction upon which a metal washer 18 is seated after a felt washer 19 has been placed upon the bolt. The shoulder 17 and washer 18 limit the inward movement of the head 11 of the bolt, and the felt washer, which is under compression when the base is assembled upon the support, firmly presses the base 6 against the heads 11 of the bolts.

Fig. 4 illustrates a further modification of the fastening device. A standard bolt is provided with upstrucl; lugs 21. which constitute a seat for a metal washer The lugs and washer limit inward movement of the head 11 of the bolt 9 and. therefore. function similarly to the sleeve 12 illustrated in Figs. 1 and 2. A spring washer 14 serves to press the base against the heads of the bolt.

iihile I have illustrated and described but three embe, nents of my invention will be apparent to those skilled in the art that various changes, modifications, substi-- tutions, additions and omissions may be made therein withcut departing from the spirit and scope of my lHJOlll'lOil, as forth in the a ended claims.

I claim as my invention:

1. A fastening member for securing a base member to a support comprising a bolt having an enlarged portion for engaging the base and limiting outward movement thereof with respect to the support, means limiting inward movement of the energed portion, and a yielding means between the base and the support for y'eldingly pressing the base into engagement with the enlarged portion of the bolt and retaining the base in spaced relation to the support.

2. A fastening member for securing a base member to a support comprising a bolt threaded at one end for receiving a threaded nut and having an enlarged portion for engaging the base and limiting outward move ment thereof with respect to the support, a sleeve on the shank of the bolt for limiting inward movement of the enlarged portion thereof, a nut for the bolt and a yielding means between the base and the support for yieldingly pressing the base into engagement with the enlarged portion of the bolt and retaining the base in spaced relation to the support.

3. A fastening member for securing a perforate base member to a support having a perforation aligned with a perforation in the base comprising a threaded bolt extending through the said perforations for clamping the base to the support, means for fixing the head of the bolt in a predetermined spaced relation to the support for permitting movement of the base longitudinally of the bolt, and a yielding means between the base and the support for yieldingly pressing the base into engagement with the head of the bolt and for retaining the base in spaced relation to the support.

t. A fastening member for securing a perforate base member to a support having a perforation aligned with a perforation in the base, comprising a threaded bolt extending through the said perforation for clamping the base to the support, a sleeve surrounding the bolt for positioning the head of the bolt in a predetermined fixed spaced relation to the support permitting movement of the base longitudinally of the bolt and a spring washer on the bolt between the base and the support for yieldingly pressing the base into engagement with the head of the bolt and for retaining the base in spaced relation to the support.

5. The combination with a perforate support and a base member having a plurality of perforations aligned with those in the support, of bolts extending through the aligned perforations and having base-engaging portions that will not pass through the perforations, means for spacing the said portions a predetermined distance from the support, and yielding means between the base and support for yieldingly retaining the base in engagement with the said portions.

In testimony whereof, I have hereunto subscribed my name this first day of July,

WILLARD H. KEMPTON. 

